Narrative:

Prior to landing, landing gear on the amphibious floats are in the down and locked position. 4 green lights confirm this, backed up by 2 visual inspections. Upon normal touchdown, rollout started and experienced no abnormal indications until airplane veered slightly to the left. After approximately 300-400 ft rollout, noticed rapid deceleration to a full stop. Upon visual inspection, main gear had collapsed. Contacted tower and informed them of the situation. Callback conversation with reporter revealed the following information: reporter states that the aircraft is C206G. The amphibious gear system is quite old. It is an engine driven pneumatic system. His mechanic explained that the system has probably not been taken out in over 20 yrs. It has been annualed, but that is inspecting and lubricating only. Reporter feels the whole system is poor as there are no mirrors mounted to see the gear is extended. Newer aircraft have such a system. In the older system the knob to extend the gear is placed down for gear extension then put in the neutral position after gear down indication. This does not leave any pressure in the system. The newer installations have a knob which remains in the down position until the landing and once off the runway the knob is placed in the neutral position. A better procedure according to the reporter.

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Original NASA ASRS Text

Title: AMPHIBIOUS ACFT C206G WITH GEAR EXTENDED HAS ACFT VEER TO THE L AND STOP THE ROLLOUT AFTER ABOUT 350 FT. THE MAIN GEAR HAD COLLAPSED.

Narrative: PRIOR TO LNDG, LNDG GEAR ON THE AMPHIBIOUS FLOATS ARE IN THE DOWN AND LOCKED POS. 4 GREEN LIGHTS CONFIRM THIS, BACKED UP BY 2 VISUAL INSPECTIONS. UPON NORMAL TOUCHDOWN, ROLLOUT STARTED AND EXPERIENCED NO ABNORMAL INDICATIONS UNTIL AIRPLANE VEERED SLIGHTLY TO THE L. AFTER APPROX 300-400 FT ROLLOUT, NOTICED RAPID DECELERATION TO A FULL STOP. UPON VISUAL INSPECTION, MAIN GEAR HAD COLLAPSED. CONTACTED TWR AND INFORMED THEM OF THE SIT. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR STATES THAT THE ACFT IS C206G. THE AMPHIBIOUS GEAR SYS IS QUITE OLD. IT IS AN ENG DRIVEN PNEUMATIC SYS. HIS MECH EXPLAINED THAT THE SYS HAS PROBABLY NOT BEEN TAKEN OUT IN OVER 20 YRS. IT HAS BEEN ANNUALED, BUT THAT IS INSPECTING AND LUBRICATING ONLY. RPTR FEELS THE WHOLE SYS IS POOR AS THERE ARE NO MIRRORS MOUNTED TO SEE THE GEAR IS EXTENDED. NEWER ACFT HAVE SUCH A SYS. IN THE OLDER SYS THE KNOB TO EXTEND THE GEAR IS PLACED DOWN FOR GEAR EXTENSION THEN PUT IN THE NEUTRAL POS AFTER GEAR DOWN INDICATION. THIS DOES NOT LEAVE ANY PRESSURE IN THE SYS. THE NEWER INSTALLATIONS HAVE A KNOB WHICH REMAINS IN THE DOWN POS UNTIL THE LNDG AND ONCE OFF THE RWY THE KNOB IS PLACED IN THE NEUTRAL POS. A BETTER PROC ACCORDING TO THE RPTR.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.